Figured I should weigh in. I fly the Admiral Quackbar, a hearty girl that refuses to die.
I used to run symmetrical. I still would if I wasn't in the Ducks. However, since I now generally fly with a full team and not alone, I've taken to a ship made for complimenting kills instead of snatching them myself. My left side is the meta kill side, gat below, mortar above. My right so is my blender side, double carronades. On the front I throw on an artemis.
My right side is the complimentary side. The carronades give me a wide range of abilities. Knocking out the balloon is well and good, but what people often don't realize is a carronade can disable components effectively and aren't too bad for stripping armor. This combined with an artemis on the front makes for a mean disable. However, this isn't the deathblow to an enemy ship. My complimentary ship is. With a balloon down and engines barely functional my allied ship's power is increased. Suddenly every gat / mortar shot that would have hit the balloon is now hitting the armor. Its simple in idea, increases effectiveness with good crew, and has delivered me good results.
Generically speaking, just remember that Junkers are three man ships. With three people working together with well defined jobs, they won't let you down. You have great repair abilities combined with good firepower leaving you with a fantastic ship.